Filler cap



July 9, 1968 F. SHAW 3,391,817

FILLER CAP Filed July 19, 1967 6 Sheets-Sheet 1 FIG. 1

Q a Q NVENTOR.

RANCIS SHAW E BY ATTORNEYS F. SHAW 3,391,817

July 9, 1968 FILLER CA? 6 Sheets-Sheet 2 Filed July 19, 1967 53 5? s7 s9,7 f I FIG.8 BY

INVENTOR FRANCIS SHAW July 9, 1968 F. SHAW 3,391,817

FILLER CAP Filed July 19, 1967 6 Sheets-Sheet 5 22 INVENTOR. I FRANCISSHAW ATTORNE YS July 9, 1968 Filed July 19, 1967 FIG.7

F. SHAW 3,391,817

FILLER CAP 6 Sheets-Sheet 4 K 54 I 56 es s5 s7 67 INVENTOR. FRANCIS SHAWATTORNEYS F. SHAW July 9, 1968 FILLER CAP 6 Sheets-Sheet 5 Filed July19, 1967 INVENTOR. FRANCIS SHAW FIG. 9

FILLER CAP Filed July 19, 1967 6 Sheets-Sheet 6 avian 7a,?

Fm us 51101 a. a l- 2 United States Patent ABSTRACT OF THE DISCLOSURE Afiller cap for a tank having an opening defined by an annular wall, thecap having a plug member with an outwardly extending flange at its upperend, a sealing member disposed about the periphery of the plug memberbelow the flange, a retaining member positioned below the sealing memberfor holding the sealing member in place, a locking mechanism disposedbelow the plug member, and an operating shaft extending through the plugmember and connected to the locking mechanism for moving the lockingmechanism toward the plug member when the cap is disposed within theopening to lock the cap in such opening with the flange of the plugengaging against the upper end of the wall surface of the opening andthe sealing member against the annular wall surface of such opening.

CROSS REFERENCE TO RELATED APPLICATION This application is acontinuation-in-part of applicants copending application, Ser. No.496,574 filed Oct. 15, 1865.

BACKGROUND OF THE INVENTION Field of the invention This inventionpertains to filler caps for tanks such as gas tanks and moreparticularly to a manually operable filler cap constructed to seal theopening of the tank and to dissipate any electrical charge contactingthe outer surface of the cap.

Description of the prior art In providing a filler cap for the gasolinetank of an airplane, for example, it is desirable that the cap bemanually operable so that it may be removed when refueling is necessaryand also securely locked into the tank opening after refueling withoutnecessitating the use of specialized tools. It is further desirable thatthe filler cap be constructed in such a way whereby visual observationof the cap will readily show whether it is properly locked into thetank. In addition, these caps have to be constructed to meet rigidspecifications and standards and this is particularly true where thecaps are to be used in airplanes. They must be able to withstand anyinternal pressure created within the tank, must not vibrate loose duringuse, and where the tank will contain explosive fumes such as created byhigh octane gasoline, it is of utmost importance that the filler cap belightning safe, that is, immune to electrical sparking on the fuel sideof the point of seal without adversely affecting the sealing function ofthe cap.

In the past, filler caps of this general type have been constructed witha plug member for effecting a sealing with the tank opening and acooperating locking mechanism depending therefrom for locking the caponto the tank in a sealed position. A shaft extending through the plugmember is attached at its lower end to the locking mechanism andprovided at its upper end with an actuating handle adapted to bereceived within a handle recess formed in the upper surface of the plugmember. Move- F CC ment of the handle into and out of the recess willcause longitudinal movement of the locking mechanism relative to theplug member while rotation thereof about the axis of the shaft will movethe locking mechanism from a first position in which the cap may bereadily removed from the tank opening to a second position where thelocking mechanism may be moved toward the plug member to securely lockthe cap in sealed relationship within the opening. I

For receiving caps of this construction, the tank is provided with anadapter member which defines the tank opening. This adapter isconstructed with an annular wall surface extending into the tank forreceiving the plug member and an annular locking flange at the bottom ofthe wall surface. The annular flange is provided with openings or slotsfor permitting the locking mechanism to pass beyond it when the cap isinserted into the adapter so that the locking mechanism may then berotated about the axis of the plug and into a position under the flangewhereby movement of the locking mechanism toward the plug member willcause it to engage against the undersurface of the flange and lock thecap in sealed position within the tank opening.

With filler caps of this construction, the sealing of the plug memberagainst the annular Wall of the adapter member is effected by means ofan O-ring fixed to the outer surface of the plug member. This O-ringextends beyond the outer periphery of the plug member and in some caseseffects a spacing of the upper surface of the plug member from thesurrounding adapter member and tank wall when the cap is oriented inlocked position within the tank opening. This does not prevent a propersealing of the cap but does expose the sealing O-ring to the ambientatmosphere rendering it more susceptible to deterioration. Also, byhaving the exposed outer surface of the cap spaced from the surroundingadapter and outer wall of the tank, a situation is created in which anelectrical charge striking directly against the cap or passing from theouter wall surface of the tank onto the cap may tend to more readilypass through the cap and inwardly into the tank rather than across thecap and back onto the outer surface of the tank. It is apparent that anyelectrical charge entering the tank and creating internal sparking,where for example the tank contains gasoline, may cause the tank toexplode.

SUMMARY OF THE INVENTION In accordance with the teachings of the presentinvention, the filler cap is constructed so that its exposed uppersurface seats directly upon the adapter defining the tank opening. inaddition, the sealing of the cap within the tank opening is effected bya compressible seal in the form of an O-ring positioned about theperiphery of the plug member. As the cap is locked into the tankopening, this O-ring is deformed into positive engagement with theopposed annular wall portion of the adapter and the flange of the plugmember is seated directly upon the end of the annular wall of theadapter. To activate the seal member, it is positioned on the plugmember of the cap in alignment with a slanted portion of the adaptermember so that insertion of the cap into the opening will cause thesealing member to engage against the annular wall surface of the adapterat this slanted portion. Alternatively, a compression plate may beattached to the bottom of the plug member and slidably received over itslower end whereby upon locking of the cap into the opening, suchcompression member will be drawn into engagement with the O-ring tocompress it and thereby cause it to deform outwardly of the plug memberand into engagement with the annular wall surface of the adapter.

Upon insertion of the cap into the opening, the locking mechanismdisposed at the lower end of the cap will be drawn upwardly and intoengagement with the lower portion of the adapter. This locking mechanismmay be constructed to effect either rigid or resilient lockingconnection with the adapter. In one embodiment of the invention, thelocking mechanism is constructed with compressible locking surfaces forcooperating with the locking flangeof the adapter member so that it willmaintain a positive locking engagementwith the adapter flange over alimited range of movement relative to the plug member and flange. Thisassures that a positive locking of the cap within the opening will beeffected when the operating handle has been moved fully into the handlerecess of the plug member. In another embodiment, the entire lockingstructure is comprised of a single resilient spring member which, uponactuation, moves radially outwardly of the cap and into underlyingengagement with the adapter to lock the cap within the tank opening.

BRIEF DEESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view of thefiller cap and tank adapter;

FIG. 2 is a cross-sectional view of the filler cap in locked positionwithin a tank opening;

FIG. 3 is a cross-sectional view of the filler cap positioned within thetank opening in release position;

FIG. 4 is a top plan view of the filler cap as shown in FIG. 2;

FIG. 5 is .a cross-sectional view taken through lines 5-5 of FIG. 2;

FIG. 6 is a cross-sectional view taken through lines 66 of FIG. 3;

FIG. 7 is an exploded view of a modified embodiment of the filler cap ofthe present invention;

FIG. 8 is a cross-sectional View of the cap of FIG. 7 in locked positionwithin the tank opening;

FIG. 9 is a cross-sectional view of still another embodiment of thefiller cap of the present invention in locked position within the tankopening;

FIG. 10 is a cross-sectional view of the cap of FIG. 9 in releaseposition within the tank opening;

FIG. 11 is a cross-sectional view of still another embodiment of thefiller cap of the present invention in locked position within the tankopening; and

FIG. 12 is a plan view of the lower end of the filler cap shown in FIG.11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, the fillercap of the present invention comprises a plug member 1 having an outercylindrical periphery 2 disposed intermediate its upper and lower ends 3and 4, respectively. Upwardly of the cylindrical surface 2 is anoutwardly extending frusto-conical flange 5. The lower end of thecylindrical surface 2 terminates in a transverse flange 6 facing thelower end of the plug member. Below this flange member, the surface 7 ofthe plug member 1 is of reduced diameter and the lower end of the plugmember is recessed as shown at 8. Extending downwardly from the plugmember in the recessed area are a plurality of aligning studs 9. Asshown in FIG. 2, the plug member is provided with a centrally locatedbore 10 extending from the lower recessed portion 8 into a handle recess11 formed in the upper end of the plug member.

' Cooperating with the plug member is a compression member 12. Thiscompression member is cup-shaped and is slidably received over the lowerend of the plug member. The uppermost surface of the compression memberdefines an annular surface 13 facing the flange 6 of the plug member.Apertures 14 extend through the comp-ression member for receiving thealigning studs 9 of the plug memberhExtending downwardly from thecompression member is a stem 15 of reduced diameter. A centrally locatedbore 16 extends through the compression member and is adapted to be inalignment with the bore 10 of the plug member when the two parts areassembled as shown in FIG. 2. Along the outer peripheral surface of thecompression member are a plurality of positioning lugs 17. These lugsextend downwardly from the compression member and are adapted tocooperate with'an adapter member attached to the tank opening as morefully described below. A compressible sealing member comprised of arubber O-ring 18 is positioned between the flange portion 6 of the plugmember and the annular surface 13 of the compression member as shown inFIG. 2.

A locking support 19 in the form of a plate is secured to the lower endof the stem portion of the compression member and is provided withlocking fingers 20 disposed radially outwardly of the main body portionof the locking plate. These fingers extend in a direction upwardlytoward the plug member and terminate in an upper surface 21. Acompressible locking means in the form of a leaf spring member 22 isattached to each of the locking fingers in a bowed relationship relativeto its upper surface so as to leave a gap between the spring and theassociated locking finger. As shown in FIG. 1, these leaf springs areformed from a unitary spoked member. Alternatively, however, they may beformed individually for attachment to the'locking fingers. A centrallylocated slot 24 is provided in the locking plate which is adapted to bein alignment with the bores 10 and 16 of the plug member and compressionmember when the parts are in assembled condition.

For connecting all of the parts of the filler cap together, an operatingshaft member 25 is provided. This shaft member has a reduced upper endportion 26 passing through the plug member about which is positioned asealing O-ring 27 for effecting a seal between the shaft and the plugmember. The O-ring is held in position about the shaft portion byseating within a groove 28. A compression spring 29 surrounds the shaftintermediate the plug member and compression member and normally urgesthese members apart. The lower end of the shaft passes through the stem15 of the compression member and is provided with a flattened portion 30for reception into the complementary-shaped slot 24 of the lockingplate. The end of the shaft is threaded as at 31 and a nut 32 and washer33 are provided for securely attaching the locking plate to the bottomof the shaft. The lower end of the shaft is provided with an aperture 34extending transversely therethrough to which may be secured a lanyard(not shown). This lanyard may be of polyurethaneor other suitablematerial and is connected at its other end to the tank for preventingcomplete removal of the cap from the tank beyond the extent permitted bythe lanyard.

For operating the cap, an actuating handle 35 is pivotally attached tothe operating shaft at its upper end for movement about an axis 36extending crosswise of the shaft. A washer member 37 is located on thebottom of the handle recess about the shaft 25 to provide a bearingsurface for the handle as more fully described below.

The shaft member 25 when secured in place by the nut 32 may be rotatedrelative to the plug and compression members but due to the flattenedsurface 30, the locking plate is fixed for rotation with the shaft. Inaddition, the shaft is fixed against movement longitudinally of thelocking plate but is free to slide longitudinally through the bore 10 inthe plug member.

The filler cap as described above is received within a suitable adaptermember 38 which is connected to the tank 38 as by means of the rivets39. This adapter member defines the opening in the tank; and as shown inFIGS. 1 and 2, is provided with an annular wall portion 40 extendingdownwardly from the upper surface 41. At the lowermost end of the wallportion 40, a locking flange 42 extends toward the center of theopening. This flange,

as shown in FIG. 1, is slotted at points spaced circumferentiallytherearound. The slots are each comprised of two sections with thesections disposed nearest the wall 40 defining positioning slots 43 andthose disposed adjacent the inner periphery of the flange defininglocking slots 44.

In attaching the filler cap to the adapter, the handle 35 is pivotedabout the axis 36 to the vertical position shown in FIG. 3. This permitsthe compression plate and clamping plate to move in a direction awayfrom the plug member under the influence of the spring 29. With thehandle in this raised position, it is turned until it abuts against anend surface 45 of the finger recess 11. In turning the handle about theaxis of the shaft, it will ride over a raised rib 46 on the washermember 37 and i this rib will assist in holding the handle in positionagainst the surface 45. When the handle is in this position, the lockingfingers 20 will be in alignment with the downwardly extendingpositioning lugs 17 of the compression member and the filler cap may bereadily inserted into the opening defined by the annular wall surface ofthe adapter with the lugs 17 disposed within the slots 43 and with thelocking fingers 21 disposed directly below the slots 44. This is therelease position of the adapter as shown in FIGS. 3 and 6.

Once the filler cap has been inserted into the opening as shown in FIG.3, the handle 35 is then rotated about the axis of the shaft to rotatethe shaft and the locking plate until the handle engages another surface47 of the handle recess 11. In this position, the enlarged wing portions48 of the handle will be in alignment with the complementary-shapedportions of the recess 11 so that the handle may be rotated about theaxis 36 downwardly into the recess 11. This rotation of the handle aboutthe axis 36 will cause the compression member 12 to be drawn upwardlyagainst the action of the spring 29 due to a camming action effectedbetween a camming surface 49 on the lower portion of the handle and theupper surface of the plug member in the area of the washer 37. As thecompression member is drawn upwardly, the locking fingers will engagethe undersurface of the flange portion 42 of the opening and assure thatthe plug member will be drawn downwardly into the adapter with theoutwardly extending flange 5 seated directly against the rounded upperend of the adapter as shown at 50. As the compression member is drawntoward the plug member, the O-ring 18 is compressed between the flange 6of the plug member and the annular surface 13 of the compression member.This compression deforms the -ring and presses it outwardly into sealingengagement with the annular wall surface of the opening. As the handleis being rotated about the axis 36 and downwardly into the handle recess11, the leaf springs 22. disposed on the locking fingers engage againstthe undersurface of the flange 42 of the adapter as shown at 52 in FIG..2; and due to the compressibility of the leaf springs, it is possibleto obtain a tight locking of the filler cap within the adapter over alimited range of longitudinal movement of the locking plate. If theseleaf springs were not provided, final engagement of the locking fingers20 with the flange 42 at 52 and of the flange of the plug member withthe adapter 38 at 50 would have to be effected at the same moment thatthe undersurface 51 of the handle engages the bottom of the recess 11.If this engagement were effected before the handle surface 51 engagedthe bottom of the recess, further movement of the handle downwardly inthe recess would be prevented due to the rigid connection at 50 and 52.If, on the other hand, engagement were not effected at 50 and 52 whenthe surface 51 of the handle was seated against the bottom of therecess, a loose connection would be etfected. This, of course, isundesirable. The leaf springs 22 provided a degree of tolerance inaddition to that otherwise present due to permissible deflection of thelocking flange 42 and permit the locking fingers to positively engagethe flange 42 before the handle is fully rotated into the recess; yet,because of the compressibility of these springs, further rotation of thehandle is permitted to properly position it within the recess 11.

FIG. 7 shows a modified embodiment of the filler cap of the presentinvention in which all of the exposed parts that are positioned belowthe point of sealing of the cap within the tank opening are constructedof non-conductive material such as plastic to further prevent thepossibility of sparking within the tank. This cap is comprised of a plugmember 53 having an outer cylindrical periphery 54 upwardly of which isan outwardly extending flange 55. The lower end of the cylindricalsurface terminates in a transverse flange 56; and below this flange thesurface of the plug member is grooved at 57 for receiving an O-ring seal58. Thc plug on its undersurface is provided with a plurality ofaligning apertures 59; and a bore 60 extends centrally through the plugmember and into a handle recess 64.

Positioned below the plug member is a compression member or plate 65which, like the compression member shown in FIG. 1, is cup-shaped andslidably received over the lower end of the plug member. The uppermostsurface of the compression member 65 is provided with an annular surface66 which faces the flange 56 of the plug member; and a plurality ofaligning studs 67 extending upwardly from the compression member intothe apertures 59 of the plug member. The compression plate is alsoprovided with a central bore 68 adapted to be in alignment with the bore60 of the plug member when the two parts are assembled as shown in FIG.8. A positioning lug 69 located at the periphery of the compressionplate extends downwardly therefrom in the same manner as the lugs of thecap shown in FIG. 1. The lug 69 is adapted to cooperate with the slot 70of the adapter member 71 attached to the tank opening to preventrotation of the plug and compression members once they are inserted intothe tank opening.

Below the compression member there is located a locking support or plate72. This locking plate is provided with a plurality of locking fingers73 similar to the locking fingers 20 of the plate shown in FIG. 1. Thefingers are positioned radially outwardly of the plate and extend in anupward direction toward the compression and plug members.

The parts of the cap assembly shown in FIG. 7 are connected together bymeans of an operating shaft member 74. This shaft extends from thehandle recess 64 of the plug member through the compression member andbeyond the lower end of the locking member. An operating handle 75 whichis of similar construction to the handle shown in FIG. 4 is connected tothe upper end of the shaft and is adapted to be received within thehandle recess. In order to hold the parts of the cap on the shaft, 2.locking cap 76 is provided. This cap is made of suitable material whichis non-conductive such as plastic and has positioned therein a nut 77which is adapted to be threaded upon the lower end of the shaft 74. Thenut is molded directly into the locking cap 76 in a nonrotativerelationship therewith so that the parts of the cap may be secured tothe shaft by simply attaching the locking cap onto the end of the shaftdisposed below the locking plate.

The cap shown in FIG. 7 is operated in essentially the same manner asthe cap shown in FIG. 1. The shaft 74 is rotated about its own axis tobring the locking fingers 73 into and out of alignment with the slots ofthe adapter member. When the locking fingers are brought into suchalignment, the handle will be in a raised position; and in order to holdthe handle in this position so that one may readily observe that the caphas not been locked in the tank opening, a compressible rubber ring 78is positioned about the shaft 74 between the compression member 65 andthe locking support 72. This compression ring, which is made of materialnot affected by the contents of the tank, normally urges the lockingsupport in a downward direction and thus urges the shaft 74 in adownward direction. With the shaft urged in this direction, the handlewill be held in its raised vertical position once the surface 75' hasbecome seated on the bottom of the handle recess.

When it is desired to lock the cap into the tank opening, the handle isfirst rotated about the axis of the shaft to position the lockingfingers under the inwardly directed flange 79 of the adapted member asshown in FIG. 8. Next the handle is rotated about its pivotal connectionto the shaft 74 and into the handle recess. This movement draws thecompression member 65 upwardly against the O-ring 58 to deform itoutwardly into engagement with the annular wall surface 80 of theadapter; and at the same time, the locking fingers 73 of the plate 72are brought into locking engagement with the flange 79 of the adapter.During this movement of the locking plate, the compressible rubber ring78 is compressed between the plate and the compression member 65 andassumes the shape shown in FIG. 8. To prevent the rubber ring 78 frominterfering with the shaft 74 and to prevent the ring itself frombecoming damaged by the movement of the shaft, a spacer member 81 isdisposed between the shaft and the rubber ring.

In the embodiment of the invention shown in FIGS.

7 and 8, the plug member is made of die cast aluminum while theoperating shaft is made of steel. The compression member 65, lockingmember 72 and the locking cap 76 are each made of plastic material andthus all of the exposed parts of the cap positioned below the sealingring 58 are of nonconductive material thereby preventing the creation ofsparking in the interior of the tank.

FIGS. 9 and illustrate another embodiment of the present invention inwhich the complete actuation of all of the parts of the cap is effectedby rotation of the handle member in one direction about an axisextending crosswise of the shaft. As shown in FIGS. 9 and 10, the cap iscomprised of a plug member 82 similar to that shown in FIG. 8. The plugmember is provided with a sealing ring 83 which is adapted to bedeformed outwardly thereof by the compression member 84. The compressionmember along its lower peripheral surface is provided with a taperedsurface 85; and both the plug member and compression member are heldtogether in assembled condition by means of an operating shaft 86extending from a handle recess 87 formed in the plug member downwardlybeyond the compression member. An operating handle 88 is pivotallyattached to the shaft 86 at its upper end for rotation about the axis 89extending crosswise of the shaft. A locking nut 90 is threaded onto theexposed lower end of the shaft 86 to hold the plug and compressionmembers together. The shaft 86, however, extends beyond the nut 90 andreceives a locking spring member 91 at a point below the compressionmember 84. This spring member is held against removal from the shaft bymeans of a seat member in the form of a nut 92 but is free to slideupwardly of the shaft. The spring member extends diametrically acrossthe compression plate and at each free end is provided with a curvedcamming surface 93 adapted to ride along the tapered surface 85 of thecompression memher. The extreme ends of the spring 91 extend radiallyfrom the curved surfaces to form locking fingers 94.

The cap shown in FIGS. 9 and 10 is adapted to be received within anadapter member 95 having an annular wall surface 96. As shown in FIG.10, the spring member 91 is normally disposed within the outer peripheryof the compression member when the handle is oriented in a verticalreleased position and the curved surfaces 93 of the spring engage thetapered surface 85 of the compression member to urge the shaft 86 in adownward direction and thus hold the handle in this vertical position.With the parts of the cap so oriented, the cap may be readily insertedinto the adapter member 95. To lock the cap within the tank and seal theO-ring against the annular wall 96 of the adapter, the handle is rotateddownwardly about the axis 89 and into the handle recess 87. With thismovement of the handle, a camming action is effected between the handlesurface 97 and the bottom of the handle recess to draw the shaft in anupward direction. This brings the nut into engagement with thecompression member and draws it upwardly to compress and deform theO-ring 83 outwardly into sealing engagement with the annular wall of theadapter. At the same time, the nut 92 draws the spring member upwardlyand the curved surfaces 93 follow along the tapered surface 85 of thecompression member. The spring member, and in particular the lockingfingers 94, are thus caused to move radially outwardly of thecompression member and into locking engagement with the undersurface ofthe adapter. Because of the compressibility of the spring member,initial contact of the fingers 94 with the adapter member may beeffected before the operating handle 88 has been fully rotated into thehandle recess so as to assure a positive locking of the cap within thetank opening.

FIGS. 11 and 12 show another modified embodiment of the filler cap .ofthe present invention in which all of the exposed parts positioned belowthe point of sealing of the cap in the tank opening are constructed ofnonconductive material such as plastic to prevent the possibility ofsparking within the tank. This cap is comprised .of a plug member 101constructed of a suitable conductive material such as die cast aluminumhaving an outer cylindrical periphery 102 upwardly of which is anoutwardly extending flange 103. Disposed below the flange 103 andencircling the periphery 102 of the plug member is an O-ring seal 104.An aligning aperture 105 is provided on the lower surface of the plugmember and a bore 106 extends centrally through the plug member and intoa handle recess 107.

Positioned below the plug member is a retaining member 108. Thisretaining member is provided with an aligning post 109 adapted to bereceived within the aligning aperture in the lower surface of the plug.Also, the retaining member, which as shown in FIG. 11 as beingcupshaped, is provided with a radially inwardly extendingcircumferential rib 110. This rib is adapted to cooperate with acomplementary-shaped groove 111 formed in the outer periphery of thelower end portion of the plug member so as to hold the retaining memberonto the plug member. The upper outer surface of the retaining memberprovides an annular surface 112 facing the lower surface of the flange103 of the plug member. This annular surface holds the sealing ring 104in position on the plug member.

Extending downwardly from the retaining member at the periphery thereofare a plurality of positioning lugs 113 shown in FIG. 12. These lugs areadapted to cooperate with slots 114 of the adapter member 115 which isattached to the tank opening so as to prevent rotation of the plug andretaining members once the cap is inserted into the tank opening. 7

Below the retaining member is located a locking member or plate 116.This locking plate is provided with a plurality of locking fingers 117,shown in FIG. 12, similar to the locking fingers 20 of the plate shownin FIG. 1. The fingers are positioned radially outwardly of the plateand extend in an upward direction toward the retaining and plug membersof the cap.

The parts of the cap are connected together by means of an operatingshaft 118. This shaft extends from the handle recess 107 of the plugmember through the retaining member and beyond the lower end of thelocking plate. An operating handle 119 which is similar to theconstruction of the handle shown in FIG. 4 is pivotally connected to theupper end of the operating shaft and is adapted to be received withinthe handle recess. In order to hold the parts of the cap on the shaft, asecuring means in the form of a locking cap 120 is attached to theexposed lower end of the operating shaft. Also, in assembling the partsof the cap together, a compression spring 121 is provided. Thiscompression spring is positioned in encircling relationship with respectto the shaft between the plug member and locking plate so as to normallyurge the locking plate away from the plug and retaining members.

As indicated above, all the parts of the cap disposed below the point ofsealing to the adapter are constructed of non-conductive material. Forthis purpose, the retaining member is made of a suitable plastic such asthat sold by duPont under the tradename Zytel 101. In addition, thelocking plate 116 has an interior skeleton framework 122 of die castaluminum which is coated on its exposed surfaces with a suitable plastic123 such as Zytel 101. Similarly, the locking cap 120 is constructed ofa non-conductive material such as Zytel 101. In the construetion of thecap shown in FIGS. 11 and 12, the operating shaft is constructed ofstainless steel and in order to isolate it and the compression springfrom the interior of the tank, a non-conductive washer 124 is positionedbetween the retaining member and locking plate in encirclingrelationship with the compression spring as shown in FIG. 11. Thiswasher may be constructed of a suitable material such as nylon, Also, asimilar washer 125 is positioned between the lower surface of thelocking plate and the locking cap; and the locking cap when secured tothe exposed lower end of the operating shaft seals against the lowersurface of the locking plate and isolates the lower end of the operatingshaft from the interior of the tank.

The cap shown in FIGS. 11 and 12 is operated in a similar manner to thatof the cap shown in FIG. 1. The shaft 118 is rotated about its own axisto bring the locking fingers into and out of alignment with the slots ofthe adapter member. When the locking fingers are brought into suchalignment, the handle will be in a raised position and held in thisposition by the compression spring 121.

When it is desired to lock the cap in the tank opening, the handle isfirst rotated about the axis of the shaft to position the lockingfingers 117 under the inwardly directed flange 126 of the adapter memberas shown in FIG. 12. For permitting rotation of the locking plate, theportion 127 of the shaft surrounded by the locking plate is flattenedand received within a complementaryshaped slot 128 in the locking plate.Next, the handle 119 which is pivotally connected to the operating shaftat 129 is rotated about this pivotal connection and into the handlerecess 107. This movement draws the fingers of the locking plateupwardly into engagement with the lower surface of the flange 126 of theadapter and at the same time draws the plug member 101 downwardly intothe opening. Upon downward movement of the plug member into the opening,the sealing ring 104 engages against the annular wall surface of theadapter along an inwardly and downwardly directed surface 130 until theflange 103 comes into direct contact with the upper end of the annularwall surface of the adapter as shown at 131.

In will be apparent from the above that removal of the cap from the tankwill be effected by operating in the reverse manner from that describedabove. In order to prevent misplacement or loss of the cap when removedfrom the tank opening, it is preferably connected to the adapter memberby a suitable lanyard 132. One end of the lanyard is connected to theadapter at 133 while the other end extends in sealing relationshipthrough a slot in the locking cap 120 and is connected to the lower endof the operating shaft as at 134. This lanyard is constructed ofpolyurethane or other suitable non-conductive material.

The above is a description of the preferred embodiments of the presentinvention; however, it is to be understood that various changes may bemade without departing from the scope of the invention as set forth inthe following claims.

I claim:

1. A filler cap for a tank having an opening defined by an annular wallsurface extending into said tank, said cap comprising:

(a) a plug member having:

(1) upper and lower ends,

(2) an outer peripheral surface intermediate its ends adapted to bereceived within said opening in opposed relationship with respect to theannular wall surface thereof,

(3) an outwardly extending flange disposed adjacent to the upper endthereof and adapted to seat directly against the upper end of the Wallsurface of said opening;

(b) a retaining member received over the lower end of said plug belowsaid flange and having:

(1) an annular surface facing said flange;

(c) sealing means disposed between said flange and said annular surfacefor compression and distortion between said peripheral surface of saidplug member and the annular wall surface of said opening;

(cl) locking mechanism disposed below said retaining member; and

(e) a movable operating shaft extending through said plug member fromthe upper end thereof and operatively connected to said lockingmechanism for moving said locking mechanism into an operative lockingposition to lock said cap within the opening of said tank and forsimultaneously drawing the flange of said plug member into directcontact with said upper end of the wall surface of the opening and thesealing means into sealing engagement with said annular wall surface.

2. A filler cap according to claim v1 wherein:

(a) said retaining member is slidably received over the lower end ofsaid plug for movement toward and away therefrom; and

(b) said retaining member is operatively connected to said lockingmechanism for axial movement therewith into compressive engagement withsaid sealing means to deform the latter outwardly of the peripheralsurface of said plug member and into said sealing engagement with theannular wall surface of said opening upon movement of said lockingmechanism into said locking position.

3. A filler cap according to claim 1 wherein:

(a) the annular wall surface of said opening against which said sealingmeans engages extends radially inwardly of said opening at an acuteangle relative to the longitudinal axis of said plug member and theoperating shaft thereof.

4. A filler cap according to claim 3 wherein:

(a) said plug member is constructed of electrically conductive material;

(b) said retaining member has an outer lower surface of non-conductivematerial with the upper annular surface thereof engaging against saidsealing means to isolate the outer peripheral portion of said plugdisposed below said sealing means from the interior of said tank;

(0) said locking mechanism is constructed with its exposed "surface ofnon-conductive material; and

(d) non-conductive securing means is attached to the lower end of saidoperating shaft in enclosing relationship therewith for securing saidlocking mechanism to said shaft with the lower end thereof isolated fromthe interior of said tank.

5. A filler cap according to claim 4 further including:

(a) means disposed between said plug and said locking mechanism andnormally urging said plug and looking mechanism away from each other.

6. A filler cap according to claim 5 wherein:

(a) said means comprises a compression spring encircling said operatingshaft between said plug and locking mechanism for normally urging saidplug and locking mechanism away from each other; and

(b) the upper surface of said locking mechanism and the lower surface ofsaid plug include non-conductive axially opposed portions engaging eachother upon movement of the locking mechanism into said locking positionto isolate said compression spring from the interior of said tank.

7. A filler cap for a tank having an opening defined by an annular wallsurface extending into said tank, said cap comprising:

(a) a plug member having:

(1) upper and lower ends,

(2) an outer peripheral surface intermediate its ends adapted to bereceived within said opening in opposed relationship with respect to theannular wall surface thereof,

(3) an inwardly extending first flange disposed adjacent to and facingthe lower end thereof,

and

(4) an outwardly extending second flange disposed adjacent to the upperend thereof and adapted to seat directly against the upper end of thewall surface of said opening;

(b) a compression member slidably received over the lower end of saidplug for movement toward and away therefrom and having:

( 1) an annular surface facing the first flange of said plug member;

() compressible sealing means disposed between said first flange andsaid annular surface for compression therebetween and distortionoutwardly of said peripheral surface of said plug member as said plugand compression members are moved toward each other;

(d) locking mechanism sion member; and

(e) a movable operating shaft extending through said plug member fromthe upper end thereof and operatively connected to said compressionmember and locking mechanism for drawing said compression member intocompressive engagement with said sealing means to deform the latteroutwardly of said peripheral surface of the plug member and for movingsaid locking mechanism into an operative position to lock said capwithin the opening of said tank.

8. A filler cap for a tank having an opening defined by an annular wallsurface extending into said tank and a flange portion extending fromsaid annular wall toward the center of said opening withcircumferentially spaced slots therein, said cap, comprising:

(a) a plug member having:

(1) upper and lower ends,

(2) an outer cylindrical surface intermediate its ends adapted to bereceived within said opening in opposed realtionship with respect to theannular wall surface thereof,

(3) an inwardly extending first flange disposed adjacent to and facingthe lower end thereof, and

(4) an outwardly extending second flange disposed adjacent to the upperend thereof and adapted to seat directly against the upper end of thewall surface of said opening;

(b) a cup-shaped compression member slidably received over the lower endof said plug for movement toward and away therefrom and having:

( 1) an annular surface facing the first flange of said plug member;

(c) compressible sealing means disposed between said first flange andsaid annular surface for compression therebetween and distortionoutwardly of the cylindrical surface of said plug member as said plugand compression members are moved toward each other;

disposed below said compres- (d) a rotatable shaft extending throughsaid plug and compression members from the upper end of said plug memberto the lower end of said compression member in slidable and sealedrelationship with re spect to said plug member;

(e) means disposed between said plug and compression members fornormally urging said members away from each other;

(f) a locking support operatively connected to said shaft for rotationtherewith at a position below said said compression member;

(g) a plurality of locking fingers fixed to said locking support at aposition disposed radially outwardly thereof with respect to thelongitudinal axis of said shaft, said fingers extending in an upwarddirection toward said compression member and being adapted to passthrough and beyond the slots in the flange portion of said tank openingin one position of rotation of said shaft; and

(h) actuating means connected to the upper end of said shaft forrotating said locking support about the axis of said shaft upon rotationof said shaft to a second position and for drawing said compressionmember and locking support upwardly relative to i said plug member uponupward longitudinal movement of said shaft in said second position ofrotation to compress said sealing means and deform it outwardly of thecylindrical surface of the plug member and to bring said locking fingersinto locking engagement with said flange portion of said opening.

9. A filler cap for a tank having an opening defined by an annular wallsurface extending into said tank'and a flange portion extending fromsaid annular wall toward the center of said opening withcircumferentially spaced slots therein, said cap comprising:

(a) a plug member having:

(1) upper and lower ends,

(2) an outer cylindrical surface intermediate its ends adapted to bereceived within said opening in opposed relationship with respect to theannular wall surface thereof; and

(3) an outwardly extending flange disposed adjacent the upper endthereof and adapted to seat directly against the upper end of the wallsurface of said opening;

(b) sealing means connected to the outer cylindrical surface of saidplug member below said flange and extending radially outwardly thereofto seal said plug member against the annular wall surface of saidopening; 1

(c) a rotatable shaft extending through said plug member in slidable andsealing relationship therewith;

(d) locking plate operatively connected to said shaft for rotationtherewith at a position below said plug member;

(e) spring means disposed between said plug member and said lockingplate for normally urging said plate away from said plug member;

(f) a plurality of locking fingers fixed to said locking plate at aposition located radially outwardly thereof with respect to thelongitudinal axis of said shaft, said fingers extending in an upwarddirection toward said plug member and being adapted to pass through andbeyond the slots in the flange portion of said tank opening in oneposition of rotation; and

(g) a handle pivotally connected to said shaft about an axis extendingcross-wise thereof at the upper end of said plug member for rotatingsaid shaft to a second position about its axis to move said fingersunder and into longitudinal alignment with the flange portion of saidopening and having a camming surface in operable engagement with theupper end of said plug member for drawing said locking plate 13 towardsaid plug member upon rotation of the handle about said crosswise axiswhen said shaft is disposed in said second position of rotation.

10. A filler cap according to claim 9 further compnsmg:

(a) compressible locking means disposed on the upper surfaces of saidlocking fingers and facing toward said compression member.

11. A filler cap according to claim wherein:

(a) said compressible locking means are comprised of resilient springmembers positioned over said locking fingers in bowed relationship.

12. A filler cap for a tank having an opening defined by an annular wallsurface extending into said tank, said cap compnsmg:

(a) a plug member having:

(1) upper and lower ends,

(2) an outer peripheral surface intermediate its ends adapted to bereceived within said opening in opposed relationship with respect to theannular wall surface thereof, and

(3) an inwardly extending flange facing the lower end thereof;

(b) a compression member slidably received over the lower end of saidplug for movement toward and away therefrom and having:

(1) an annular surface facing the flange of said plug member;

(c) compressible sealing means disposed between said flange and saidannular surface for compression therebetween and distortion outwardly ofsaid peripheral surface af said plug member as said plug and compressionmembers are moved toward each other;

(d) locking mechanism disposed below said compression member;

(e) compressible means disposed between said compression member and saidlocking mechanism for normally urging said locking mechanism in adownward direction away from said compression member; and

(f) a movable operating shaft extending through said plug member fromthe upper end thereof and operatively connected to said compressionmember and locking mechanism for drawing said compression member intocompressive engagement with said sealing means to deform the latteroutwardly of said peripheral surface of the plug member and for movingsaid locking mechanism into an operative position to lock said capwithin the operating of said tank.

13. A filler cap for a tank having an opening defined by an annular wallsurface extending into said tank and a flange portion extending fromsaid annular wall toward the center of said opening withcircumferentially spaced slots therein, said cap comprising:

(a) a plug member having:

(1) upper and lower ends,

(2) an outer cylindrical surface intermediate its ends adapted to bereceived within said opening in opposed relationship with respect to theannular wall surface thereof,

(3) an inwardly extending first flange disposed adjacent to and facingthe lower end thereof, and

(4) an outwardly extending second flange disposed adjacent to the upperend thereof and adapted to seat directly against the upper end of thewall surface of said opening;

(b) a compression member disposed below said plug member for movementtoward and away therefrom and having;

( 1) an annular surface facing the first flange of said plug member;

(c) compressible sealing means disposed between said first flange andsaid annular surface for compression therebetween and distortionoutwardly of the cylindrical surface of said plug member as said plugand compression members are moved toward each other,

(d) a rotatable shaft extending through said plug and compressionmembers from the upper end of said plug member to the lower end of saidcompression member in slidable and sealed relationship with respect tosaid plug member;

(e) a locking support operatively connected to said shaft for rotationtherewith at a position below said compression member;

(f) means disposed between said compression member and said lockingsupport for normally urging said locking support away from saidcompression member and said shaft in a downward direction;

(g) a plurality of locking fingers fixed to said locking support at aposition disposed radially outwardly thereof with respect to thelongitudinal axis of said shaft, said fingers extending in an upwarddirection toward said compression member and being adapted to passthrough and beyond the slots in the flange portion of said tank openingin one position of rotation of said shaft; and

(h) actuating means connected to the upper end of said shaft forrotating said locking support about the axis of said shaft upon rotationof said shaft to a second position and for drawing said compressionmember and locking support upwardly relative to said plug member uponupward longitudinal movement of said shaft in said second position ofrotation to compress said sealing means and deform it outwardly of thecylindrical surface of the plug member and to bring said locking fingersinto locking engagement with said flange portion of said opening.

14. A filler cap according to claim 13 wherein:

(a) said actuating means comprises:

(1) a handle pivotally connected to said shaft at the upper end of saidplug member for movement about an axis extending crosswise of said shaftand having a camming surface in operable engagement with the upper endof said plug for drawing said compression member and locking supporttoward said plug member upon rotation of the handle about the transverseaxis when said shaft is disposed in said second position of rotation.

15. A filler cap according to claim 14 wherein:

(a) said compressible means between said compression member and saidlocking mechanism comprises an annular compressible rubber ringsurrounding said operating shaft.

16. A filler cap according to claim 15 wherein:

(a) said annular ring is spaced from said operating shaft by an annularspacer member.

17. A filler cap according to claim 16 wherein:

(a) said operating shaft extends downwardly beyond said lockingmechanism; and wherein (b) a locking cap is threaded onto the exposedend of the shaft in engagement with the undersurface of said lockingmechanism to hold the parts of the cap in assembled condition.

18. A filler cap according to claim 17 wherein:

(a) said locking cap includes an internally disposed nut non-rotatablyfixed therein for threaded engagement with the downwardly extending endof said operating shaft; and

(b) said locking cap, locking mechanism and compression member are allof non-conductive material.

19. A filler cap according to claim 18 wherein:

(a) said second flange is obliquely inclined toward the upper end ofsaid plug member.

20. A filler cap according to claim 19 further comprising:

(a) means connecting said plug member and compression member togetheragainst relative rotation; and

(b) positioning lugs extending downwardly from said compression memberand adapted to be positioned within the slots of the flange portion ofthe tank opening to hold said plug and compression members againstrotation relative to the annular wall portion of said opening.

21. A filler cap according to claim 20 further comprising:

(a) a handle recess in the upper end of said plug having a shapecomplementary to that of the handle for receiving said handle when saidshaft is disposed in said second position of rotation.

22. A filler cap for a tank opening having an opening defined by anannular wall surface extending into said tank, said cap comprising:

(a) a plug member having:

(1) upper and lower ends,

(2) an outer cylindrical surface intermediate its ends adapted to bereceived within said opening in opposed relationship with respect to theannular wall surface thereof,

(3) an inwardly extending first flange disposed adjacent to and facingthe lower end thereof, and

(4) an outwardly extending second flange disposed adjacent to the upperend thereof and adapted to seat directly against the upper end of thewall surface of said opening;

(b) a compression member positioned below the lower end of said plug formovement toward and away therefrom and having:

(1) an annular surface facing the first flange of said plug member, and

(2) an annular inwardly extending surface facing away from saidcompression member;

-(c) compressible sealing means disposed between said first flange andsaid annular surface for compression therebetween and distortionoutwardly of said cylindrical surface of said plug member as said plugand compression members are moved toward each other;

-(d) a movable operating shaft extending through the plug member fromthe upper end thereof, through the compression member, and downwardlytherebeyond for movement in an axial direction;

(e) a locking mechanism disposed below said compression member andcomprising:

(1) a generally U-shaped spring member positioned on said shaft at apoint spaced from said compression member with camming surfaces adjacenteither end engaging the tapered annular surface of said compressionmember and radially outwardly extending locking fingers; and

(f) means for securing said compression member and locking mechanism tosaid shaft for movement therewith in an upward direction to move saidcompression member toward said plug member and to slide the cammingsurfaces of said locking mechanism upwardly along the annular surface ofsaid compression member and said locking fingers outwardly of thecylindrical surface of said plug member.

23. A filler cap according to claim 22 further comprising:

(a) an operating handle pivotally attached to the upper end of saidoperating shaft in a vertical position when said shaft is moved to itsdownward position and having a camming surface engaging the uppersurface of said plug member for moving said shaft in said upwarddirection as said handle is rotated downwardly toward said plug member.

24. A filler cap according to claim 23 wherein:

(a) said means for securing said locking mechanism to said shaftcomprises a seat member connected to said shaft below said lockingmechanism; and

(b) said spring member is positioned between said compression member andsaid seat member to normally urge said shaft in a downward directionwhen said handle is in a vertical position to retain the handle in saidposition.

References Cited UNITED STATES PATENTS 3,006,489 10/1961 Corbett 220-43,173,570 3/1965 De Pew 220-40 3,343,707 9/1967 De Pew et al. 220253,351,226 11/1967 Hogan et al. 22025 THERON E. CONDON, Primary Examiner.

G. T. HALL, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Francis Shaw errorappears in the above identified It is certified that atent are herebycorrected as patent and that said Letters P shown below:

Column 1, line 33, "1865" should read 1965 Column 5, line 72, "provided"should read provide Signed and sealed this 23rd day of December 1969.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, I r.

Attesting Officer Commissioner of Patents

